A tapered roller bearing is characterized by having a larger load capacity and a higher rigidity than any other roller bearing of the same size.
FIG. 13 is an axially sectional view showing a tapered roller bearing in the related art. As shown in FIG. 13, a tapered roller bearing 100 has an inner ring 101, an outer ring 102, a plurality of tapered rollers 103 rollably placed between the inner and outer rings 101 and 102, and an annular retainer 104 retaining the tapered rollers 103 circumferentially at equal intervals (for example, see Patent Literature 1).
The retainer 104 has a small diameter annular portion 105, a large diameter annular portion 106, and a plurality of columnar portions 107 laid between the two annular portions 105 and 106. In addition, in the retainer 104, pockets 108 for receiving the tapered rollers 103 are constituted by the two annular portions 105 and 106 and adjacent ones of the columnar portions 107.